pbiancardi

2000 Jeep Cherokee Limited
165,000 miles

I have completed:

Rusty's 3" Advanced Lift Kit
Iron Rock Double Shear Adjustable Track Bar
Iron Rock Sway Bar Links
Changed Plugs and boots.
Seafoam Treatment (brake booster line)
Complete rust repair (any rust spot anywhere was Chassis Saver treated)
Removed carpet (left out), repaired one floor pan.
Brown Dog Motor Mounts (to be installed with header)
Head is not cracked (replaced by my mechanic for PO 5,000 miles ago, along with head bolts, valve cover gaskets, camshaft, lifters, thermostat, timing chains, gears, timing gasket, cooling fan motor, and hoses).

She still runs a little rough and loud (more than normal I suspect). I am assuming the manifold is cracked (it looks original) and also that the Catalytic Converter is probably somewhat clogged (also looks original). I have no CEL or major problems.

I already ordered the Thor Cowl Intake Kit (I know no real performance gains but it sounds and looks cool).

I want to get -

Headers or Manifold with flex joints, any suggestions and if there is no real performance gains I guess I would be looking for the cheapest ones that will last and not crack.

Catalytic Converter, any suggestions (bolt on please) and is there anything to be gained from a high flow model?

If anyone can point me to the preferred parts I would greatly appreciate, I have searched but a lot of what I find is old and I'm not sure if still valid. Thanks in advance.

Fred/N0AZZ

Do you have emissions testing in your state?

Also on the 00-01 they have 4 sensors and depend on some of the things your considering changing, all of them go to the PCM control.

pbiancardi

Yes Indiana and we have emissions testing.

cleenrob

Well dont get an APN header. Mine leaks like a ****, im replacing it with a Borla long tube header soon I expect that to be a much better unit

Ianf406

I dont have emissions testing but my AFE twisted steel header has been great. I just incorporated a flex pipe on the down pipe. I use a high flow spun cat- Purchased it from mudfrog on the forum and it has also held up great. If you contact him, he can guide you in the right direction for the 2000. Great prices.

The Borla kit is nice- had it on a previous XJ. I don't know if it's pricetag is justified by its niceness but too each their own. Ive also had a Gibson set and they held up for along time.

extrashaky

Your header options are limited in a 2000 because of the emissions package that was introduced that year. I would suggest you read this thread:

https://www.cherokeeforum.com/f67/wh...rmance-199115/

It even has pictures.

In 2000 there was an option between the California emissions and the EPA emissions. CA vehicles have three catalytic converters and four O2 sensors. EPA vehicles have one catalytic converter with two O2 sensors. In 2001 they went entirely to CA emissions.

I have an EPA 2000 XJ. My down pipe has no cats in it, but it fits in the exact same location as the catted down pipe.

APN headers will not fit the 2000 anyway without extra work. You can't really make them work at all with the CA emissions vehicles. You'd have to have a new down pipe made to make it work with the EPA version.

LAF1269

Since when does Indiana have emissions testing?

EDIT: Further research shows that you must live in Lake or Porter Counties. Those of us in the rest of the state are exempt. That is one STUPID rule.

SeriousOffroad

http://www.seriousoffroadproducts.co...-GASKETS-BLACK

I can add flex connectors to my site if you or anyone else is interested.

I spent a lot of time researching "Hi-flow" cats....save your money.

Ianf406

While I rarely disagree with you, I do on this. A "high flow" cat has less substrate per inch which in turn provides less resistance and more free flowing air. Like blowing through a sheet vs a sleeping bag. The 100/200/300 cell count cats definitely flow better than a stock which has 700-800 cells. The same principle applies as an air filter... more flow=less filtration. Sure more toxins get out but if we really cared we wouldn't be driving 20 year old lifted Jeeps.

Being as they cost the same or are cheaper as a regular cat (less material), are still legal and are freer flowing, why not? The HF Spun cats are also smaller with nothing to really catch on and being spun gives them a smoother/easier flowing surface than one that is cribbed on the inside.. While your statement may have been true 20 years ago, there are indeed cats that flow more freely now. I tore into my stock one and couldn't believe how many layers and such were in there...

SeriousOffroad

http://www.catalyticconverter.org/ne...erter-&News=89

pbiancardi

So no worry about that one cracking? Point me to the cat you recommend and you have a sale, thanks.

Ianf406

Yup that same page has been passed around for about 10 years with no dyno numbers, no tests. They even say:

" In theory, an aftermarket cat is higher flow than it's*O.E. counterpart, because the*O.E. converter has*a substrate made up of*700 cells per square inch, so the exhaust flow with an aftermarket converter is a little freer, but not dramatically! "

That is not a theory, its not rocket science... less that half the resistance is freer flowing air and in a cheaper more compact unit. Read further and you will discover they happen to not sell high flow cats and are thus not recommending them.

Do a quick Google search on highflow cat vs standard and there are guys that have dynoed their sport cars with no cats/OEM/HF and while they are working with more HP, the results are substantial.

To each their own. I am happy with mine but cant really say it did anything as I did the entire thing (Stroker/headers/3"exhaust etc. ) at once.

Ianf406

The rugged ridge header has great reviews for longevity. There are better performing headers but its probably not worth 2x the price on a 4.0. Serious's price is as good as anywhere and he is active on the forum with great reviews so you can't go wrong there!

cleenrob

Well im picking mine up used for half price. I rarely by stuff brand new lip

Ianf406

Thats awesome!